From e873c74132f0c5f1452816cd9bb26208f0bba1e1 Mon Sep 17 00:00:00 2001 From: Shivank Garg Date: Sat, 22 Aug 2026 19:22:05 +0000 Subject: dmaengine: fix use-after-free in dma_chan_put() and dma_release_channel() When dma_device_put() drops the last reference on chan->device->ref, dma_device_release() runs and may free the dma_device along with its channels. dma_chan_put() then still reads chan->device->owner via dma_chan_to_owner() for the trailing module_put(). KASAN catches it: slab-use-after-free in dma_chan_put+0x3e6/0x4c0 Read of size 8 by task insmod/6319 Freed by task 6319: kfree+0x225/0x470 dma_chan_put+0x395/0x4c0 dmaengine_put+0xf8/0x160 Cache the module owner in dma_chan_put() before the put so the trailing module_put() does not need chan->device. Fixes: 8ad342a86359 ("dmaengine: Add reference counting to dma_device struct") Suggested-by: Sashiko Link: https://sashiko.dev/#/patchset/20260518-dmaengine-kref-fix-v1-1-4d6125048fb7@amd.com Reviewed-by: Frank Li Reviewed-by: Logan Gunthorpe Signed-off-by: Shivank Garg Link: https://patch.msgid.link/20260822-dmaengine-kref-fix-v5-3-d4a4ee47d927@amd.com Signed-off-by: Vinod Koul --- tools/perf/util/util.h | 126 +++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 126 insertions(+) create mode 100644 tools/perf/util/util.h (limited to 'tools/perf/util/util.h') diff --git a/tools/perf/util/util.h b/tools/perf/util/util.h new file mode 100644 index 000000000..87a0818a8 --- /dev/null +++ b/tools/perf/util/util.h @@ -0,0 +1,126 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef __PERF_UTIL_H +#define __PERF_UTIL_H + +#define _BSD_SOURCE 1 +/* glibc 2.20 deprecates _BSD_SOURCE in favour of _DEFAULT_SOURCE */ +#define _DEFAULT_SOURCE 1 + +#include +#include +#include +#include +#include +#include +#include +#ifndef __cplusplus +#include +#endif + +extern const char perf_usage_string[]; +extern const char perf_more_info_string[]; + +extern const char *input_name; + +/* This will control if perf_{host,guest} will set attr.exclude_{host,guest}. */ +extern bool exclude_GH_default; + +extern bool perf_host; +extern bool perf_guest; + +/* General helper functions */ +void usage(const char *err) __noreturn; + +struct dirent; +struct strlist; + +int mkdir_p(char *path, mode_t mode); +int rm_rf(const char *path); +int rm_rf_perf_data(const char *path); +struct strlist *lsdir(const char *name, bool (*filter)(const char *, struct dirent *)); +bool lsdir_no_dot_filter(const char *name, struct dirent *d); + +size_t hex_width(u64 v); + +int sysctl__max_stack(void); + +bool sysctl__nmi_watchdog_enabled(void); + +int perf_tip(char **strp, const char *dirpath); + +void cpumask_to_cpulist(char *cpumask, char *cpulist); + +void print_separator2(int pre_dash_cnt, const char *s, int post_dash_cnt); + +#ifndef HAVE_SCHED_GETCPU_SUPPORT +int sched_getcpu(void); +#endif + +#ifndef HAVE_SCANDIRAT_SUPPORT +int scandirat(int dirfd, const char *dirp, + struct dirent ***namelist, + int (*filter)(const struct dirent *), + int (*compar)(const struct dirent **, const struct dirent **)); +#endif + +extern bool perf_singlethreaded; + +void perf_set_singlethreaded(void); +void perf_set_multithreaded(void); + +char *perf_exe(char *buf, int len); + +#ifndef O_CLOEXEC +#ifdef __sparc__ +#define O_CLOEXEC 0x400000 +#elif defined(__alpha__) || defined(__hppa__) +#define O_CLOEXEC 010000000 +#else +#define O_CLOEXEC 02000000 +#endif +#endif + +struct perf_debuginfod { + const char *urls; + bool set; +}; +void perf_debuginfod_setup(struct perf_debuginfod *di); + +const char *perf_basename(const char *path); + +char *filename_with_chroot(int pid, const char *filename); + +int do_realloc_array_as_needed(void **arr, size_t *arr_sz, size_t x, + size_t msz, const void *init_val); + +#define realloc_array_as_needed(a, n, x, v) ({ \ + typeof(x) __x = (x); \ + __x >= (n) ? \ + do_realloc_array_as_needed((void **)&(a), \ + &(n), \ + __x, \ + sizeof(*(a)), \ + (const void *)(v)) : \ + 0; \ + }) + +static inline bool host_is_bigendian(void) +{ +#ifdef __BYTE_ORDER__ +#if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__ + return false; +#elif __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__ + return true; +#else +#error "Unrecognized __BYTE_ORDER__" +#endif +#else /* !__BYTE_ORDER__ */ + unsigned char str[] = { 0x1, 0x2, 0x3, 0x4, 0x0, 0x0, 0x0, 0x0}; + unsigned int *ptr; + + ptr = (unsigned int *)(void *)str; + return *ptr == 0x01020304; +#endif +} + +#endif /* __PERF_UTIL_H */ -- cgit v1.3.1